I'm apparently in danger of being blocked from asking anymore questions if I ask any others without checking they are OK so I felt it best to ask whether a question about Mozilla Thunderbird, namely about setting the folders incoming items are sent to, would be appropriate for this website.
To quote the Help Center:
Super User is for computer enthusiasts and power users. If you have a question about …
- computer hardware,
- computer software, or
- personal and home computer networking
Mozila Thunderbird on Windows 7 definitely falls into that category, as long as the question is "practical, answerable questions based on actual problems that you face".